#include "riscv_const_structs.h"
#include "ref.h"

void ref_cfft_f32(const riscv_cfft_instance_f32 *S, float32_t *p1,
                  uint8_t ifftFlag, uint8_t bitReverseFlag)
{
    int n, mmax, m, j, istep, i;
    float32_t wtemp, wr, wpr, wpi, wi, theta;
    float32_t tempr, tempi;
    float32_t *data = p1;
    uint32_t N = S->fftLen;
    int32_t dir = (ifftFlag) ? -1 : 1;

    // decrement pointer since the original version used fortran style indexing.
    data--;

    n = N << 1;
    j = 1;
    for (i = 1; i < n; i += 2) {
        if (j > i) {
            tempr = data[j];
            data[j] = data[i];
            data[i] = tempr;
            tempr = data[j + 1];
            data[j + 1] = data[i + 1];
            data[i + 1] = tempr;
        }
        m = n >> 1;
        while (m >= 2 && j > m) {
            j -= m;
            m >>= 1;
        }
        j += m;
    }
    mmax = 2;
    while (n > mmax) {
        istep = 2 * mmax;
        theta = -6.283185307179586f / (dir * mmax);
        wtemp = sinf(0.5f * theta);
        wpr = -2.0f * wtemp * wtemp;
        wpi = sinf(theta);
        wr = 1.0f;
        wi = 0.0f;
        for (m = 1; m < mmax; m += 2) {
            for (i = m; i <= n; i += istep) {
                j = i + mmax;
                tempr = wr * data[j] - wi * data[j + 1];
                tempi = wr * data[j + 1] + wi * data[j];
                data[j] = data[i] - tempr;
                data[j + 1] = data[i + 1] - tempi;
                data[i] += tempr;
                data[i + 1] += tempi;
            }
            wr = (wtemp = wr) * wpr - wi * wpi + wr;
            wi = wi * wpr + wtemp * wpi + wi;
        }
        mmax = istep;
    }

    // Inverse transform is scaled by 1/N
    if (ifftFlag) {
        data++;
        for (i = 0; i < 2 * N; i++) {
            data[i] /= N;
        }
    }
}

void ref_cfft_q31(const riscv_cfft_instance_q31 *S, q31_t *p1, uint8_t ifftFlag,
                  uint8_t bitReverseFlag)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)p1;
    float32_t fSrc[S->fftLen * 2];
    riscv_q31_to_float(p1, fSrc, S->fftLen * 2);
    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q31 data, cast to float, scale down for float
        fSrc[i] = (float32_t)p1[i] / 2147483648.0f;
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, ifftFlag,
                         bitReverseFlag);
            break;
    }

    if (ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            p1[i] = (q31_t)(fSrc[i] * 2147483648.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            p1[i] = (q31_t)(fSrc[i] * 2147483648.0f / (float32_t)S->fftLen);
        }
    }
}

void ref_cfft_q15(const riscv_cfft_instance_q15 *S, q15_t *pSrc, uint8_t ifftFlag,
                  uint8_t bitReverseFlag)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)pSrc;
    float32_t fSrc[S->fftLen * 2];
    riscv_q15_to_float(pSrc, fSrc, S->fftLen * 2);

    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q15 data, cast to float, scale down for float, place in
        // temporary buffer
        scratchArray[i] = (float32_t)pSrc[i] / 32768.0f;
    }

    for (i = 0; i < S->fftLen * 2; i++) {
        // copy from temp buffer to final buffer
        fSrc[i] = scratchArray[i];
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, ifftFlag,
                         bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, ifftFlag,
                         bitReverseFlag);
            break;
    }

    if (ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f / (float32_t)S->fftLen);
        }
    }
}

void ref_cfft_radix2_f32(const riscv_cfft_radix2_instance_f32 *S, float32_t *pSrc)
{
    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }
}

void ref_cfft_radix2_q31(const riscv_cfft_radix2_instance_q31 *S, q31_t *pSrc)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)pSrc;
    float32_t fSrc[S->fftLen * 2];
    riscv_q31_to_float(pSrc, fSrc, S->fftLen * 2);

    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q31 data, cast to float, scale down for float
        fSrc[i] = (float32_t)pSrc[i] / 2147483648.0f;
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }

    if (S->ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            pSrc[i] = (q31_t)(fSrc[i] * 2147483648.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            pSrc[i] = (q31_t)(fSrc[i] * 2147483648.0f / (float32_t)S->fftLen);
        }
    }
}

void ref_cfft_radix2_q15(const riscv_cfft_radix2_instance_q15 *S, q15_t *pSrc)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)pSrc;
    float32_t fSrc[S->fftLen * 2];
    riscv_q15_to_float(pSrc, fSrc, S->fftLen * 2);

    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q15 data, cast to float, scale down for float, place in
        // temporary buffer
        scratchArray[i] = (float32_t)pSrc[i] / 32768.0f;
    }

    for (i = 0; i < S->fftLen * 2; i++) {
        // copy from temp buffer to final buffer
        fSrc[i] = scratchArray[i];
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }

    if (S->ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f / (float32_t)S->fftLen);
        }
    }
}

void ref_cfft_radix4_f32(const riscv_cfft_radix4_instance_f32 *S, float32_t *pSrc)
{
    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, pSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }
}

void ref_cfft_radix4_q31(const riscv_cfft_radix4_instance_q31 *S, q31_t *pSrc)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)pSrc;
    float32_t fSrc[S->fftLen * 2];
    riscv_q31_to_float(pSrc, fSrc, S->fftLen * 2);

    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q31 data, cast to float, scale down for float
        fSrc[i] = (float32_t)pSrc[i] / 2147483648.0f;
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }

    if (S->ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            pSrc[i] = (q31_t)(fSrc[i] * 2147483648.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q31, cast to q31
            pSrc[i] = (q31_t)(fSrc[i] * 2147483648.0f / (float32_t)S->fftLen);
        }
    }
}

void ref_cfft_radix4_q15(const riscv_cfft_radix4_instance_q15 *S, q15_t *pSrc)
{
    uint32_t i;
    // float32_t *fSrc = (float32_t*)pSrc;
    float32_t fSrc[S->fftLen * 2];
    riscv_q15_to_float(pSrc, fSrc, S->fftLen * 2);

    for (i = 0; i < S->fftLen * 2; i++) {
        // read the q15 data, cast to float, scale down for float, place in
        // temporary buffer
        scratchArray[i] = (float32_t)pSrc[i] / 32768.0f;
    }

    for (i = 0; i < S->fftLen * 2; i++) {
        // copy from temp buffer to final buffer
        fSrc[i] = scratchArray[i];
    }

    switch (S->fftLen) {
        case 16:
            ref_cfft_f32(&riscv_cfft_sR_f32_len16, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 32:
            ref_cfft_f32(&riscv_cfft_sR_f32_len32, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 64:
            ref_cfft_f32(&riscv_cfft_sR_f32_len64, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 128:
            ref_cfft_f32(&riscv_cfft_sR_f32_len128, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 256:
            ref_cfft_f32(&riscv_cfft_sR_f32_len256, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 512:
            ref_cfft_f32(&riscv_cfft_sR_f32_len512, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 1024:
            ref_cfft_f32(&riscv_cfft_sR_f32_len1024, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 2048:
            ref_cfft_f32(&riscv_cfft_sR_f32_len2048, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;

        case 4096:
            ref_cfft_f32(&riscv_cfft_sR_f32_len4096, fSrc, S->ifftFlag,
                         S->bitReverseFlag);
            break;
    }

    if (S->ifftFlag) {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f);
        }
    } else {
        for (i = 0; i < S->fftLen * 2; i++) {
            // read the float data, scale up for q15, cast to q15
            pSrc[i] = (q15_t)(fSrc[i] * 32768.0f / (float32_t)S->fftLen);
        }
    }
}
